This invention relates generally to communication systems and, more particularly, to an amplifier circuit for a communication device such as a radio, scanner, citizens band transceiver or the like. More particularly, the present invention relates to an improved amplifier circuit for increasing the gain for radio frequency signals by more than twenty decibels.
The present invention has a particular utility in conjunction with communication devices such as radios, scanners and citizens band transceivers utilized in a vehicle such as an automobile or a truck. Thus, the invention will be described in that context. However, the principles of the present invention may be utilized in all forms of communications systems and may be utilized with permanent installations such as in the home as well as in mobile installations such as in vehicles.
The communications industry is well aware of the difficulty of reception of radio frequency signals in certain areas because of the strength of the signal. Thus, in the so called fringe areas, there is great difficulty in receiving a sufficiently strong radio signal. In addition, with respect to citizens band transceivers, the power limitations imposed on mobile units by the Federal Communications Commission effectively limit the range of these devices to fifty miles or less depending upon terrain and other factors which would create interference. Hence in areas of high density structures such as high rise apartment buildings and office buildings, a range of one mile or less is not uncommon for citizens band transceivers.
The present invention overcomes these problems by boosting or amplifying the incoming signal by at least twenty decibels which is a power amplification of one thousand percent. Thus, an incoming signal is amplified an additional ten times by the present invention.